This invention relates generally to crop harvesting headers attachable to combines and, more particularly, to an interlock mechanism interconnecting the reel and a fore-and-aft adjustable cutterbar.
Typically, a header for a harvesting machine includes a cutterbar which is operable to cut standing crop as the machine moves forward and a rotatable reel which carries tines to engage the standing crop and sweep it towards the cutterbar for cutting and then carry the cut material towards an auger before releasing it. The auger usually consolidates the cut crop material centrally of the header before it is passed to the body of the machine for processing. The relationship between the cutterbar and the auger is critical and in general depends on the type and condition of the crop to be harvested. When harvesting down crops, i.e., crops that are not standing in a normal upright position, the relationships between the reel, the cutterbar and the auger is equally critical and, in general, the reel should be disposed so that the path described by the outer ends of the tines first enters below the level of the cutterbar forwardly thereof for lifting down crop, then sweeps closely over the cutterbar and finally passes in close proximity along the auger.
Headers are known in which the cutterbar is vertically flexible along its length so that it can follow local irregularities in the ground. With such headers, it is necessary to be able to adjust the height of the reel relative to the highest point of the cutterbar at any given instant, otherwise the cutterbar is likely to foul the reel on flexing with consequential damage to one or both components. To this end, headers having flexible cutterbars have been fitted with means for automatically adjusting the position of the reel on vertical flexure of the cutterbar.
Headers, such as shown in U.S. Pat. No. 4,011,709, have been provided to render the cutterbar adjustable in a generally fore-and-aft direction so that the spatial relationship between the auger and the cutterbar can be selectively chosen dependent on the type and condition of the crop to be harvested.